A wet blanket

Here's a few related passages from the last chapter of Thomas Merton's autobiography, The Seven Storey Mountain. Most of this chapter is about monastic life. These three excerpts are on the theme of moodiness and how it affects others:

"'Each one of you,' the Father Abbot said, 'will make the community either better or worse. Everything you do will have an influence upon others. It can be a good influence or a bad one. It all depends on you. Our Lord will never refuse you grace...'"

"It can be said, as a general rule, that the greatest saints are seldom the ones whose piety is most evident in their expression when they are kneeling at prayer, and the holiest men in a monastery are almost never the ones who get that exalted look, on feast days, in the choir. The people who gaze up at Our Lady's statue with glistening eyes are very often the ones with the worst tempers."

"[Simple, easily-contented monks] stood at the mean between two extremes. On one hand there were one or two who exagerated everything they did and tried to carry out every rule with scrupulousness that was a travesty of the real thing. They were the ones who seemed to be trying to make themselves saints by sheer effort and concentration--as if the work depended on them, and not even God could help them. But then there were also the ones who did little or nothing to sanctify themselves, as if none of the work depended on them--as if God would come along one day and put a halo on their heads and it would all be over. They followed the others and kept the Rule after a fashion, but as soon as they thought they were sick they started pleading for all the mitigations that they did not already have. And the rest of the time, they fluctuated between a gaity that was noisy and disquieting, and a sullen exasperation that threw a wet blanket over the whole novitiate."